It is often cost effective for a user who frequently travels from one office of an enterprise to another office of the enterprise, for the enterprise to route the user's calls to the office in the new location rather than forwarding the calls to the user's mobile device. Furthermore, a network may experience a service disruption, which would prohibit calls from being received.
To complicate matters, a user who frequently leaves the office may be at locations where mobile devices are not available and/or there is a poor connection. Business colleagues and other individuals who may need to contact the user are forced to forego communications with the user and/or wait until the user returns to the office. Moreover, the user may not wish to give out their mobile device number to all individuals.
Therefore, subscribers of a mobile device should register an alternative number, such as a cell phone number, a relative's phone number, or a work number at specified physical locations, that the network can use to forward calls to whenever the user leaves the office and travels to an alternate physical location.